Vibratory polisher



3, 1966 E. R. DAYTON 3,267,620

VIBRATORY POLISHER Filed Nov. 1, 1963 FIG4 INVENTOR.

EDWlN R. DAYTON A'ITO RN EYS United States Patent 3,267,620 VIBRATORY PQLISHER Edwin IR. Dayton, 48 N. Main St., South Yarmouth, Mass.

Filed Nov. 1, 1963, Ser. No. 320,865 4 Claims. (Cl. 51-163) This invention relates to polishing apparatus and more particularly to a vibratory polisher for finishing small objects such as metallic components, precious and semiprecious stones.

Many manufacturing processes have as their final step the polishing and de-burring of the work product. This is often accomplished by placing the machined components in a polishing vessel together with a suitable polishing media and thereafter rotating or vibrating the vessel. In this manner, either a tumbling or vibrating motion is imparted to the components, in turn causing them to come into vibratory or rubbing contact with one another and with the polishing media. When metal parts are subjected to this treatment, burrs and other machining irregularities are gradually worn away as the articles are polished to acquire the desired finish.

Devices of this type are also used in substantially the same manner by lapidarists in finishing precious or semi-precious stones.

When so utilized, the stones are gradually polished until extremely smooth finishes are attained. This of course contributes markedly to the value of the finished product and is of partciular importance to the treatment of inexpensive collectors items such as sea shells, beach pebbles, and the like.

The basic construction of most polishing devices presently in use usually incorporates a polishing drum mounted on a substantially horizontal shaft with a vibrating or tumbling mechanism connected thereto. Although both vibrating and tumbling polishers have been utilized extensively in the past, experience has shown that vibrating devices are superior in performance. This is due in particular to the fact that tumbling devices impart a somewhat violent tumbling motion to the articles contained therein. In so doing, delicate components are sometimes thrown against one another and damaged. In contrast, the vibrating polishers rely on a more gentle rubbing effect created by vibration, the net result being that violent action within the polishing drum is avoided. Although vibratory devices have been found superior to the tumbling devices in producing an improved polishing action, experience has shown that they are still characterized by a number of significant disadvantages. A principal disadvantage of vibratory devices presently in use is evidenced by their relatively high cost. This is in turn due to their complex designs utilizing numerous and expensive components. More particularly, these devices usually incorporate a polishing drum mounted on a shaft, the shaft being in turn journalled within expensive bearings. In addition, experience has shown that the prior art devices frequently require repairs and maintenance when continuously used over extended periods of time. Since most polishing operations extend over considerable periods of time without interruption, a dependable machine incoporating a rugged trouble-free design is of particular importance.

It is therefore a general object of the present invention to provide a vibratory polisher having an improved means of imparting vibratory motion to both the articles to be polished and the polishing media contained within the polishing drum.

Another object of the present invention is to provide a vibratory polishing device having an improved yet greatly simplified design.

A further object of the present invention is to provide a vibratory polishing device capable of being easily manufactured with a substantial reduction in cost.

Another object of the present invention is to provide a vibratory polishing device having a polishing drum suspended by spaced angularly disposed spring members between rigid standard-s extending upwardly from a fixed base.

Another object of the present invention is to provide a vibratory polishing device capable of being continuously operated for extended period of time without maintenance.

Another object of the present invention is to provide a vibratory polishing device wherein the frequency and amplitude of the vibrations imparted to the polishing drum can be easily varied and closely controlled.

These and other objects of the present invention will become more apparent as the description proceeds with the aid of the accopanying drawings in which:

FIG. 1 is a View in side elevation of the applicants apparatus with a portion of the base partially cut away to show the mechanism for imparting vibration to the polishing drum;

FIG. 2 is a view in end elevation taken along line 22 of FIG. 1;

FIG. 3 is an enlarged partial view in perspective showing the means of attaching the cradle to the standards;

FIG. 4 is a diagrammatic illustration showing the movement of the articles to be polished and polishing media within the polishing drum during operation of the applicants apparatus.

As indicated in FIGS. 1 and 2, the applicants vibratory polishing device generally indicated by the reference numeral 10 is provided with a hollow base 12 comprised of top and bottom plates 14 and 16 held in spaced relationship by front and rear members 18 and 20 and end members 22 and 24. Top plate 14 having a substantially fiat rectangular upper surface is provided with two upwardly disposed supporting standards 26 and 28 having their horizontally disposed lower portions bolted to the top plate 14 by means of bolts indicated typically at 30. As can be best seen in FIG. 2, standards 26 and 28 are positioned in a spaced oppositely disposed relationship with a first set of inwardly disposed mounting blocks 32 attached to their inner faces by means of screws indicated typically at 34.

A substantially U-shaped cradle 36 comprised of a bottom member 38 having two side extensions 40 extending upwardly therefrom is positioned between standards 26 and 28. Side extensions 40 are in turn provided on their outer faces with a second set of outwardly disposed mounting blocks 42 attached thereto by means of screws indicated typically at 44.

I The spring means used in suspending cradle 36 between supporting standards 26 and 28 will now be described with particular reference to FIG. 3. Elongated leaf spring member 46 having the upper surface of one end fixed to the lower surface of mounting block 42 by means of screws indicated typically at 48 extends horizontally therefrom with the lower surface of its other extremity attached in a similar manner to the upper surface of mounting block 32. A second identical spring member 50 is attached to one side of mounting block 32 and extends upwardly therefrom to be attached in a similar manner to the adjacent side of mounting block 42. As can be best seen in FIG. 2, a small space 52 exists between the two angularly disposed spring members 46 and 59 at their point of intersection. With this construction, it is therefore apparent that the cradle 36 is supported in a non-rotating manner between supporting standards 3 26 and 28 by the combined action of spring members do and 50.

It should of course be understood that tlthough the spring members 46 and 5t) are shown in the drawings angularly disposed at an angle of 90 with only member 50 in compression, this ange can be varied without departing from the spirit and scope of the invention in order to place both members in compression. Moreover, the vertical relationship of the mounting blocks 32 and 42 can be reversed in order to place block 42 below rather than above block 32. in so doing, the one or both of the spring members will be placed in tension rather than compression.

As indicated in the drawings, a polishing drum 5 3 is removably mounted on cradle 36. The drum is provided at each end with a raised vertically disposed key 56 Ce signed to slide within matching receiving slots 5?: cut in the inwardly disposed faces of the cradle side e:t tensions 44). With this construction, a drum can be quickly removed from the cradle for emptying and cleaning when the articles contained therein are completely polished. This is accomplished by simply grasping the drum and pulling it up in order to cause the raised keys 56 to slide out of their receiving slots 58. An alternate drum filled =wlth unpolished articles may then be quickly mounted in a similar manner on the cradle for continued polishing during this period with relatively little polishing time lost.

It should or" course be apparent that where there is no need to remove the drum, the cradle can be omitted and the mounting blocks 42 attached directly to the drum ends.

As can be best seen in H68. 1 and 2, the cradle 36 is provided with a bracket 64) attached to the lower surface of bottom member 38 by means of screws indicated typically at 6ft. Bracket 68 extends downwardly into base 12 through a passageway 62 in top plate 14. As can best be seen in PEG. 1, the lower end of bracket so is bifurcated in order to provide an elongated slot 64 extending upwardly from its lower extremity. A single throw eccentric 66 is positioned within slot 64 and mounted on the end of shaft 68 extending outwardly from motor 7h.

The total width of slot 64 is equal to the outside diameter of eccentric 66. With this relationship, as motor '70 is actuated to rotate shaft 63, the single throw eccentric 66 will be rotated within slot 64 result'ng in turn in vibratory motion being imparted to bracket 69.

Motor 74), being of the variable speed type, is connected through wire leads 72 to a rheostat 74. The rheostat is in turn provided with an upwardly dispose-d control handle terminating in a knob 76 positioned above the upper surface of a top plate 14. This of course enables the rheostat to be adjusted in order to vary the speed of motor 70 and thereby control the frequency of vibrations being imparted to bracket 68. Rheostat 74 is in turn wired to on-oii switch 78 by means of a second set of wire leads 80.

Having thus described the principal components of the applicants apparatus, its operation will now be reviewed. It should be noted at the outset that because of its inherent simplicity of construction, the applicants device is relatively light in weight and capable of being easily stored or carried to any convenient supporting surface. This is of particular importance in noncommercial applications, as for example when being utilized by amateur lapidarists. Under such circumstances, use of the device may be sporadic, obviating the necessity of a permanent installation.

In operation, the articles to be polished, be they metallic or non-metallic, together with the polishing media are simply dumped into the polishing drum 54 through a top opening indicated in FIGS. 1 and 2 by the reference numeral 82. This having been accomplished, switch 78 is turned to the on position in order to energize rheostat '74. By turning knob 7'6 to adjust the rheostat, motor 70 is actuated resulting in turn in the rotation of shaft 68 and eccentric 66.

As previously mentioned, since eccentric 66 is seated within slot 64-, its rotation will result in a vibratory motion being imparted to bracket 60. Due to the rigid structural relationship between bracl'et se and cradle 36, this vibratory motion will be transmitted directly through the cradle to the polishing rum 5a and its contents.

Cradle is excellently adapted to this vibratory mo tion due to the resilient spring means used to suspend it between the supporting standards 26 and 28. More part'cularly, as illustrated in FIG. 1, vertically disposed spring member 59 crosses horizontally disposed spring member 4-6 at a point indicated by the reference numeral 8-4. A similar point of intersection is of course provided between identical spring members at the opposite end of the cradle. With this construction, the cradle 36 receives support in both a v :tical and horizontal direction along an imaginary horizontal axis passing through both points Lid. This in turn results in all vibratory motion of cradle 36 and drum 54 occurring about this axis rather than the longitudinal axis of the drum. It should further he need that the common rotational axis of motor shaft 63 and eccentric 66 is vertically aligned with the axis of drum s4 and is offset in a horizo .1 direction from point 84.

With the aforementioned construction, it has been found that by imparting vibrations of a selected amplitude to the drum 5 1, the particles contained therein can be displaced through a path as indicated diagrammatically in PEG. 4. This results in the particles being vibrated against one another while at the same time being gently d placed in an upward direction along the inner surface Or the drum to thereafter slide back downwardly over the accumulation of particles and polishing media contained within the drum. in this manner, a gentle rubbing action is provided by both vibration and sliding, resulting in greatly increased efiiciency.

t is my intention to cover all changes and modifications of the invention herein chosen for purposes of disclosure which do not constitute departures from the spirit and scope of the invention.

1 claim:

1. A vibratory machine for use in polishing small metallic articles, precious and semi-precious stones and the like comprising the combination of: a base member having supporting standards extending upwardly therefrom in opposed spaced relationship; a polishing drum removably mounted on an intermediate cradle, said cradle suspended between said standards by spring means, said spring means comprised of two elongated bendable fiexure members, one end of each said flexure members fixed to one of said standards, said flexure members extending in spaced parallel planes with their longitudinal axes angularly disposed, the other ends of said flexure members hired to said intermediate cradle; a vibratory unit mounted on said base and connected to said polishing drum, said vibratory unit comprised of a motor mounted on said base, said motor having a rotating drive shalt extending outwardly therefrom, an eccentric mounted on said drive shaft for rotation therewith, said eccentric journalled within a bracket depending downwardly from said cradle, and means for varying the rotational speed of said motor in order to vary the frequency of vibrations imparted to said polishing drum.

2. A vibratory polishing machine comprising the combination of: a substantially horizontal base member having supporting standards extending upwardly therefrom in opposed spaced relationship, a U-shaped cradle member suspended between said standards by spring means, said spring means comprised of two elongated supporting spring members angularly disposed and extending in spaced parallel planes, one end of each said supporting spring members fixed to one of said standards, the other ends of said supporting spring members fixed to sai cradle, a polishing drum removably mounted within said cradle; and a vibratory unit mounted on said base and connected to said cradle, said vibratory unit comprising a motor mounted on said base with a rota-ting shaft extending outwardly therefrom, said shaft provided at its outwardly disposed end with an eccentric, said eccentric journalled for rotation within the lower extremity of a bracket depending from said cradle, the axis of rotation of said eccentric aligned vertically with the longitudinal axis of said drum and offset from the point of intersection of said spring members, and means for varying the rotational speed of said motor in order to vary the frequency of vibrations imparted to said polishing drum.

3. A vibratory polisher comprising the combination of: a stationary base member; spaced oppositely disposed supporting standards extending upwardly from said base member; a cradle positioned between said supporting standards, said cradle having a polishing drum removably mounted thereon; a pair of spring members at either end of said cradle for connecting said cradle to said supporting standards on an axis offset laterally from the longitudinal axis of said drum, one end of each said spring members fixed to one of said standards, said spring members extending in spaced parallel planes with their longitudinal axes angularly disposed, the other ends of said spring members attached to said cradle; and, a vibratory unit References Cited by the Examiner UNITED STATES PATENTS 1,339,818 5/1920 Gibson 259-72 2,935,714- 5/1960 Barden et al 338-157 2,973,606 3/1961 Brandt 51-463 2,997,814 8/1961 Brandt 51l63 3,093,940 6/ 1963 Balz 5l163 3,134,207 5/1964 Ferrara 51-163 3,173,664 3/1965 Isaacson et a1 51-163 HAROLD D. WHITEHEAD, Primary Examiner.

J. SPENCER OVERHOLSER, Examiner.

I. L. TATE, Assistant Examiner. 

1. A VIBRATORY MACHINE FOR USE IN POLISHING SMALL METALLIC ARTICLES, PRECIOUS AND SEMI-PRECIOUS STONES AND THE LIKE COMPRISING THE COMBINATION OF: A BASE MEMBER HAVING SUPPORTING STANDARDS EXTENDING UPWARDLY THEREFROM IN OPPOSED SPACED RELATIONSHIP; A POLISHING DRUM REMOVABLY MOUNTED ON AN INTERMEDIATE CRADLE, SAID CRADLE SUSPENDED BETWEEN SAID STANDARDS BY SPRING MEANS, SAID SPRING MEANS COMPRISIED OF TWO ELONGATE BENDABLE FLEXURE MEMBERS, ONE END OF EACH SAID FLEXURE MEMBERS FIXED TO ONE OF SAID STANDARDS, SAID FLEXURE MEMBERS EXTENDING IN SPACED PARALLEL PLANES WITH THEIR LONGITUDINAL AXES ANGULARLY DISPOSED, THE OTHER ENDS OF SAID FLEXURE MEMBERS FIXED TO SAID INTERMEDIATE CRADLE; A VIBRATORY UNIT MOUNTED ON SAID BASE AND CONNECTED TO SAID POLISHING DRUM, SAID VIBRATORY UNIT COMPRISED OF A MOTOR MOUNTED ON SAID BASE, SAID MOTOR HAVING A ROTATING DRIVE SHAFT EXTENDING OUTWARDLY THEREFROM, AN ECCENTRIC MOUNTED ON SAID DRIVE SHAFT FOR ROTATION THEREWITH, SAID ECCENTRIC JOURNALLED WITHIN A BRACKET DEPENDING DOWNWARDLY FROM SAID CRADLE, AND MEANS FOR VARYING THE ROTATIONAL SPEED OF SAID MOTOR IN ORDER TO VARY THE FREQUENCY OF VIBRATIONS IMPARTED TO SAID POLISHING DRUM. 